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Best Diesel Diagnostic Tool

Taking care of your truck and ensuring your safety on the road involves quite a few tools. There’s the electronic logging device (ELD), the dashcam, and now, the diesel diagnostic tool. 

Each one serves a special purpose, and the diagnostic tool keeps you informed about the vehicle’s operating systems. It’s a great device to have when that check engine light turns on. 

Here are several of the top diesel scanners to consider as you search for the right one for you!

Quicklook: Best Diesel Diagnostics Tools

  • Best For DPF Regenerations: The Cando HD Code II 
  • Best For Diesel Technicians: Universal Diesel Truck Diagnostic Tool 
  • Best For Owner-Operators: Diesel Handheld Scanner
  • Best For Android Users: Diesel Tablet Commercial Truck Diagnostic System
  • Best For User Friendly: FCAR F3-N

5 Best Diesel Diagnostics Tools Options

Now let’s get into the particulars of each diesel scanner and what they bring to the table.

The Cando HD Code II 

Cando is well known in the industry for developing the first handheld diagnostic tool that includes DPF regenerations, and we know how important that is to a truck’s engine. The Cando HD Code II covers commercial trucks in classes 4 through 8 and industrial engines also. This heavy-duty piece of equipment has a sleek design and is user-friendly, so you shouldn’t have much trouble learning to use it.

Best For: DPF Regenerations

Supported Protocols: OBD II

Warranty: 

  • Yes
  • 1-year manufacturer’s warranty

Power Source: Runs off the truck’s battery 

Vehicle Types Covered: 

  • Class 4-8 trucks
  • CAT Power Equipment
  • CAT Construction Equipment
  • CAT industrial Equipment

Special Features

  • DPF Regeneration
  • Code Lookup
  • Large Screen 

Benefits: 

  • Extends engine life 
  • Defines error codes  
  • Easy to read 

Disadvantages: 

  • Regens on specific engine models 

Pricing: $277

Universal Diesel Truck Diagnostic Tool Scanner

This laptop kit comes with just about everything you need to perform a thorough diagnostics test. Fully equipped with a laptop and scanner, the Universal Diesel Truck Diagnostic Tool Scanner is the perfect device for diesel technicians who need to connect with various trucks during their workday. 

Best For: Diesel Technicians

Supported Protocols: OBD II

Warranty: 

  • Yes
  • 1-year warranty on hardware
  • 2-year warranty on USB Link 2 Adapter 

Power Source: 

  • Laptop is battery-powered,
  • Scanner runs on truck’s battery 

Vehicle Types Covered: 

  • Cummins 
  • Detroit Diesel 
  • CAT 
  • Freightliner
  • Sterling
  • Peterbilt
  • Tackless
  • Charleston

Special Features

  • Pocketfleet Diagnostics 
  • Automatic VIN Decoder 
  • KnowledgeBase 
  • Technician Training

Benefits: 

  • Reads vehicle subsystems 
  • View detailed vehicle information  
  • Access to thousands of PDF guides 
  • Courses to better understand the software

Disadvantages: 

  • Expensive 
  • Bulky  

Pricing: $2,695

Diesel Handheld Scanner

This handheld unit is easy-to-use and lets you read and clear diagnostic trouble codes. It comes in a durable carry case to protect your hardware and information. 

The Diesel Handheld Scanner receives regular software updates, so you always have the latest technology at your fingertips. Take it with you on the road, and you’ll be prepared for any lights that may pop up on your dashboard.

Best For: Owner/Operators

Supported Protocols: 

  • OBD II
  • J1708 
  • J1939

Warranty: 

  • Yes
  • 1 year

Power Source: Runs on the truck’s battery 

Vehicle Types Covered: 

  • Cummins
  • Detroit Diesel
  • Isuzu
  • Mack
  • CAT
  • PACCAR
  • International Maxxforce

Special Features

  • SD Card Adapter 
  • 4 inch LCD Screen 
  • Works in temperatures between 14° and 122° F 

Benefits: 

  • View live data 
  • View freeze-frame data 
  • Read and clear codes 
  • Lifetime updates

Disadvantages: 

  • Slow to load 
  • Regens on select engines 

Pricing: $449.95

Diesel Tablet Commercial Truck Diagnostic System

The Diesel Tablet has all the advanced features you need on a sleek tablet. You won’t have to carry a huge laptop around as you move from truck to truck checking the diagnostics. 

It uses perpetual license software, so you’ll never have to worry about it expiring. You also have the option to add other Android apps to this tablet to help run your business smoothly.

Best For: Android Users

Supported Protocols: OBD II

Warranty: 

  • Yes
  • 1 year

Power Source: 

  • Tablet runs on its battery
  • Scanner runs on the truck’s battery 

Vehicle Types Covered: 

  • Cummins
  • Detroit Diesel
  • CAT
  • Volvo
  • Mack
  • Isuzu
  • PACCAR
  • CASE
  • Trackless
  • John Deere

Special Features

  • 128 GB Storage 
  • Rear-facing 8-megapixel camera 
  • Integrated Repair Information 

Benefits: 

  • Store history for multiple vehicles 
  • Take clear pictures of issues and send them to appropriate parties  
  • One tap takes you to repair information for easy navigation 

Disadvantages: 

  • Pricey 
  • Vehicle adapter only works with Diesel Tablet

Pricing: $3,499

FCAR F3-N Commercial Truck and Off-Highway Diagnostic Tool

Terms like plug-and-play and self-explanatory have been used to describe this diesel diagnostic tool. The FCAR F3-N is extremely easy for most people to use, and it syncs quickly to give you fast diagnostic reads. 

If you aren’t a technician with tons of experience, you’ll still be able to use this complete diagnostic tool without any problems. The interface is straightforward, and the features you use most are easy to find.

Best For: User-Friendly

Supported Protocols: 

  • OBD II
  • J708
  • J1939

Warranty: 

  • Yes
  • 1 year

Power Source: Runs on the truck’s battery 

Vehicle Types Covered: 

  • Mack
  • Kenworth
  • Freightliner
  • Sterling
  • Western Star
  • International
  • Peterbilt
  • Volvo
  • Bobcat
  • CASE
  • CAT
  • KOMATSU

Special Features

  • Printer and thermal printing paper included
  • 2 years of free unlimited software updates and support 

Benefits: 

  • Generate reports 
  • Device has the newest available technology  
  • View trip data 
  • Get information on components

Disadvantages: 

  • Expensive 

Pricing: $2,995

What Is a Diesel Diagnostics Tool?

A diesel diagnostic tool, also known as a diesel scanner, is a small electronic device that plugs into the truck’s On-Board Diagnostic (OBD) port to monitor the performance of the engine and emissions system and report any issues it finds. 

How Do Diesel Diagnostic Tools Work?

Once you plug the device into the OBD port, it connects with your vehicle’s computer and serves as a diagnostic code reader for trucks. It scans the engine and other vital systems for problems and reads the trouble codes. The diesel scanner then alerts the user once the issue is identified.  

What to Consider With Diesel Diagnostics Tools

You’ll find plenty of options on the market while searching for a diesel scan tool. Is a professional-grade diesel scanner necessary, or will a basic model fit your needs? Here are some things to keep in mind before finalizing your purchase.

Compatibility

Not all trucks are built the same, and different manufacturers have specific requirements for connecting devices to read your vehicle’s data. Do your research to ensure the diesel scanner has been tested for compatibility with your particular truck. Connecting a tool that wasn’t designed for your vehicle can cause more issues.

One of those issues is a Controller Area Network (CAN bus) error. Think of your truck as a human body, and the CAN bus is its nervous system. It’s how your vehicle systems communicate and connect with one another. 

If the communication between them is thrown off or read incorrectly by the diesel scan tool, you’ll have bigger problems to fix. The incorrect scanner can also blow the diagnostic fuse and cause fault codes in the vehicle’s other systems. 

Compatibility is necessary if you want the scanner to recognize all the error codes your vehicle transmits. Be sure to get a heavy-duty scanner with all the adapters and other equipment needed to read your truck’s codes correctly to save yourself from a bigger headache in the future. 

Value

Does the cost match the value of the diesel diagnostic tool? Some diesel scanners are subscription-based, and you pay monthly or yearly to maintain the services. Others are one-time purchases for the device. Both have their advantages and disadvantages depending on why you’re using the tool. 

With the one-time purchases, you won’t have to worry about additional fees, and the device will work for years to come. However, unlike subscription services that regularly update their software, the one-time purchases won’t receive remote updates. 

Also, if a newer and better device is launched, you’ll have to purchase it. With the way technology changes, that may not be cost-effective.

The subscription-based software units are equipped with cloud storage to make viewing the vehicle’s history simple, and as features are added, your device will be instantly updated. Continuous product support is offered, and you can typically use these devices on a wider range of vehicles. 

The value lies in how often you plan to use the device and whether or not it will save money in the long run. If you’re an owner-operator who just wants to check the emissions system occasionally, there’s no need to get a subscription-based service or high-end device. 

However, if you’re a fleet manager who needs to check multiple systems regularly, a subscription-based service will reduce long-term maintenance costs.  

Ease of Use

Since these devices were made with professional mechanics in mind, they can be pretty difficult to read and complex to use for the average person. However, there are scanners out there you can use that don’t require a Ph.D. in automotive diagnostics. 

You want a device that doesn’t require much effort to connect to your vehicle and has a user-friendly interface. A complex and busy system can be extremely confusing if you aren’t accustomed to using a diesel diagnostic tool. 

Also, receiving a diagnostic trouble code (DTC) without explaining what it means requires you to do more legwork to figure out the problem. An easy-to-use scanner will give you the DTC and insight into the code’s meaning. That way, if it’s something small that you know you can fix, you won’t have to take the truck to the shop.

The more advanced the scanner, the more capabilities it has. With more capabilities come more device functions, and you should want to get the most out of your diesel scanner. 

Features like clearing codes, resetting monitors, and DTC definition displays shouldn’t be buried deep in the system or difficult to read. You will avoid misdiagnosing the issues when navigating the device is simple and makes what you’re looking at and doing clear.

Reliability

You have to be able to rely on a device like a diesel diagnostic tool as it needs to be accurate when alerting you to an issue. If it’s not, you can spend money needlessly trying to fix something that was never broken. 

Another thing to look out for is a scanner that can read the car’s computer in real-time. Any delays could decrease the accuracy of the DTC. 

Electronic devices aren’t perfect, and neither are we. Mistakes will be made from time to time, usually due to human error. If that happens, you want the device’s reliability to extend to the technical support offered by the manufacturer. 

Is there someone you can call or chat online with if you’re having trouble connecting the diesel scanner or understanding fault codes? Are there instructional videos available? A dedicated technical support department is something you need your scanner to come with.

Capabilities

Each diesel diagnostic tool has its own set of features and special abilities that make it unique to the vehicles it services. You’ll have to decide exactly why you’re using a scanner to help you choose one with the features you need.

Some scanners only give you the DTC, and if you’re knowledgeable about the code meanings, this may be what you’re looking for. But if you want specific systems to be covered and more advanced functionality, you’ll need a higher-grade scanner.

Not all scanners check the transmission, battery management, or airbag system. Some scanners perform a remote diagnosis, allow you to view the report online, and complete a full system check. So if you need a device that checks tire pressure, the diesel particulate filter (DPF), and other vehicle subsystems, review the features before purchasing.  

Don’t Get Tricked by Shady Mechanics 

A diesel diagnostic tool allows you to hear and understand your truck when it needs help. Seeing the dashboard light up with different symbols while driving can be a bit concerning while you’re on the road, and you’re not always near a mechanic you trust. 

Connecting a scanner can quickly diagnose the issue and let you know if it’s something you can handle or if you need to locate a repair shop. The great thing is the shop won’t be able to pull one over on you as you’ll already have an idea of what’s causing the problem. It’s a great investment, especially if you’re on the road for days at a time. 

FAQ

What Is Diesel OBD?

It’s a system incorporated into the engine to provide self-diagnostic functionality.

Does BlueDriver Work on Diesels?

BlueDriver works with most diesel trucks, but you should double-check before using it.

What Is the Most Reliable OBD2 Scanner?

Innova has made it to the top of most lists as the most reliable OBD II scanner.

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